KABUL, Afghanistan -- Afghan security forces are now officially in charge of protecting their country from the insurgents whom the U.S.-led coalition of foreign troops has been fighting here for more than 11 years, President Hamid Karzai announced during a ceremony Tuesday, even as news broke that the Taliban were opening a long-discussed political office in Qatar, clearing a potential path to peace talks.

"This is the beginning of a new journey, so that our country, like every other country in the world, can rely on its own forces for security, manned by its own youth," Karzai said of the security handover. He was speaking during a ceremony at the sprawling new national defense university – an Afghan West Point – which is still under construction on the edge of Kabul on ground that first had to be cleared of mines. Joining him was NATO Secretary General Anders Fogh Rasmussen.

"As your forces step forward across the country, the main effort of our forces is shifting from combat to support," Rasmussen said. "We will continue to help Afghan troops in operations if needed, but we will no longer plan, execute or lead those operations. And by the end of 2014, our combat mission will be completed. At that time, Afghanistan will be fully secured by Afghans."

NATO would continue to support Afghanistan after next year with a new training, advising and assistance mission, he said.

Afterward, Karzai said he hoped the Taliban’s new office would indeed lead to peace talks. Afghanistan would send negotiators to Qatar without preconditions, he said. Still, Karzai expects that any talks begun there would quickly move onto Afghan soil, would be conducted in such a way that they end the violence in Afghanistan and wouldn’t be used by any other country to push its own interests.

The concerns of the United States and Pakistan should be considered, he said, but Afghanistan’s needs would come first.

The security transition announced Tuesday is a major milestone in the lengthy war, but it has sharply different meanings for the Afghan troops, the foreigners, the insurgents and the civilians.

The role of American and other NATO troops in the war now will be to provide the Afghan security forces with support such as training, close air support and casualty evacuation by air. That will keep some combat troops here until the end of 2014, on call if the Afghans need them.

The number of foreign troops, though, will continue to drop, with the 66,000 U.S. forces here expected to be halved by December.

A smaller contingent of troops is expected to remain after next year solely for training and support pending an agreement between foreign forces and the Afghan government.

"Last week, I was responsible for security here in Afghanistan, and today as a result of that ceremony, the responsibility is with the MOD and the MOI on behalf of President Karzai, and that is a significant change from yesterday to today," said Gen. Joseph F. Dunford Jr., the commander of U.S. and NATO forces in Afghanistan, referring to the Afghan Ministries of Defense and Interior, which control the national army and police forces.

For American troops, the war is now officially something most will experience mainly from inside massive bases, shielded from the fighting.

Their service here will look like it did during a visit by a reporter a few weeks ago to Helmand province. Helmand has been by far the most deadly place in the war for foreign troops, with more than 900 killed there, but now Afghans are almost fully in the lead for combat.